kernel/linux.git/drivers/pwm, branch v5.9.12

pwm: img: Fix null pointer access in probe

2020-10-29T09:11:54+00:00

[ Upstream commit b39c0615d0667b3a6f2f5c4bf99ffadf3b518bb1 ] dev_get_drvdata() is called in img_pwm_runtime_resume() before the driver data is set. When pm_runtime_enabled() returns false in img_pwm_probe() it calls img_pwm_runtime_resume() which results in a null pointer access. This patch fixes the problem by setting the driver data earlier in the img_pwm_probe() function. This crash was seen when booting the Imagination Technologies Creator Ci40 (Marduk) with kernel 5.4 in OpenWrt. Fixes: e690ae526216 ("pwm: img: Add runtime PM") Signed-off-by: Hauke Mehrtens Acked-by: Lee Jones Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: rockchip: Keep enabled PWMs running while probing

2020-10-29T09:11:54+00:00

[ Upstream commit 457f74abbed060a0395f75ab5297f2d76cada516 ] Following commit cfc4c189bc70 ("pwm: Read initial hardware state at request time") the Rockchip PWM driver can no longer assume a device's pwm_state structure has been populated after a call to pwmchip_add(). Consequently, the test in rockchip_pwm_probe() intended to prevent the driver from stopping PWM devices already enabled by the bootloader no longer functions reliably and this can lead to the kernel hanging during startup, particularly on devices like the Pinebook Pro that use a PWM-controlled backlight for their display. Avoid this by querying the device directly at probe time to determine whether or not it is enabled. Fixes: cfc4c189bc70 ("pwm: Read initial hardware state at request time") Signed-off-by: Simon South Reviewed-by: Uwe Kleine-König Reviewed-by: Heiko Stuebner Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

pwm: lpss: Add range limit check for the base_unit register value

2020-10-29T09:11:17+00:00

[ Upstream commit ef9f60daab309558c8bb3e086a9a11ee40bd6061 ] When the user requests a high enough period ns value, then the calculations in pwm_lpss_prepare() might result in a base_unit value of 0. But according to the data-sheet the way the PWM controller works is that each input clock-cycle the base_unit gets added to a N bit counter and that counter overflowing determines the PWM output frequency. Adding 0 to the counter is a no-op. The data-sheet even explicitly states that writing 0 to the base_unit bits will result in the PWM outputting a continuous 0 signal. When the user requestes a low enough period ns value, then the calculations in pwm_lpss_prepare() might result in a base_unit value which is bigger then base_unit_range - 1. Currently the codes for this deals with this by applying a mask: base_unit &= (base_unit_range - 1); But this means that we let the value overflow the range, we throw away the higher bits and store whatever value is left in the lower bits into the register leading to a random output frequency, rather then clamping the output frequency to the highest frequency which the hardware can do. This commit fixes both issues by clamping the base_unit value to be between 1 and (base_unit_range - 1). Fixes: 684309e5043e ("pwm: lpss: Avoid potential overflow of base_unit") Reviewed-by: Andy Shevchenko Acked-by: Thierry Reding Signed-off-by: Hans de Goede Link: https://patchwork.freedesktop.org/patch/msgid/20200903112337.4113-5-hdegoede@redhat.com Signed-off-by: Sasha Levin

pwm: lpss: Fix off by one error in base_unit math in pwm_lpss_prepare()

2020-10-29T09:11:17+00:00

[ Upstream commit 181f4d2f44463fe09fe4df02e03095cb87151c29 ] According to the data-sheet the way the PWM controller works is that each input clock-cycle the base_unit gets added to a N bit counter and that counter overflowing determines the PWM output frequency. So assuming e.g. a 16 bit counter this means that if base_unit is set to 1, after 65535 input clock-cycles the counter has been increased from 0 to 65535 and it will overflow on the next cycle, so it will overflow after every 65536 clock cycles and thus the calculations done in pwm_lpss_prepare() should use 65536 and not 65535. This commit fixes this. Note this also aligns the calculations in pwm_lpss_prepare() with those in pwm_lpss_get_state(). Note this effectively reverts commit 684309e5043e ("pwm: lpss: Avoid potential overflow of base_unit"). The next patch in this series really fixes the potential overflow of the base_unit value. Fixes: 684309e5043e ("pwm: lpss: Avoid potential overflow of base_unit") Reviewed-by: Andy Shevchenko Acked-by: Uwe Kleine-König Acked-by: Thierry Reding Signed-off-by: Hans de Goede Link: https://patchwork.freedesktop.org/patch/msgid/20200903112337.4113-4-hdegoede@redhat.com Signed-off-by: Sasha Levin

Merge tag 'pwm/for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

2020-08-14T23:00:09+00:00

Pull pwm updates from Thierry Reding: "The majority of this batch is conversion of the PWM period and duty cycle to 64-bit unsigned integers, which is required so that some types of hardware can generate the full range of signals that they're capable of. The remainder is mostly minor fixes and cleanups" * tag 'pwm/for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: pwm: bcm-iproc: handle clk_get_rate() return pwm: Replace HTTP links with HTTPS ones pwm: omap-dmtimer: Repair pwm_omap_dmtimer_chip's broken kerneldoc header pwm: mediatek: Provide missing kerneldoc description for 'soc' arg pwm: bcm-kona: Remove impossible comparison when validating duty cycle pwm: bcm-iproc: Remove impossible comparison when validating duty cycle pwm: iqs620a: Use lowercase hexadecimal literals for consistency pwm: Convert period and duty cycle to u64 clk: pwm: Use 64-bit division function backlight: pwm_bl: Use 64-bit division function pwm: sun4i: Use nsecs_to_jiffies to avoid a division pwm: sifive: Use 64-bit division macro pwm: iqs620a: Use 64-bit division pwm: imx27: Use 64-bit division macro pwm: imx-tpm: Use 64-bit division macro pwm: clps711x: Use 64-bit division macro hwmon: pwm-fan: Use 64-bit division macro drm/i915: Use 64-bit division macro

pwm: bcm-iproc: handle clk_get_rate() return

2020-07-30T09:27:13+00:00

Handle clk_get_rate() returning 0 to avoid possible division by zero. Fixes: daa5abc41c80 ("pwm: Add support for Broadcom iProc PWM controller") Signed-off-by: Rayagonda Kokatanur Signed-off-by: Scott Branden Reviewed-by: Ray Jui Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: Replace HTTP links with HTTPS ones

2020-07-30T09:27:13+00:00

Rationale: Reduces attack surface on kernel devs opening the links for MITM as HTTPS traffic is much harder to manipulate. Deterministic algorithm: For each file: If not .svg: For each line: If doesn't contain `\bxmlns\b`: For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`: If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`: If both the HTTP and HTTPS versions return 200 OK and serve the same content: Replace HTTP with HTTPS. Signed-off-by: Alexander A. Klimov Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: omap-dmtimer: Repair pwm_omap_dmtimer_chip's broken kerneldoc header

2020-07-30T09:27:12+00:00

Argument descriptions must be prepended with a '@' to be understood by the kerneldoc tooling/parsers/validators. Fixes the following W=1 warning: drivers/pwm/pwm-omap-dmtimer.c:70: warning: Function parameter or member 'dm_timer_pdev' not described in 'pwm_omap_dmtimer_chip' Cc: Tony Lindgren Cc: Joachim Eastwood Cc: NeilBrown Cc: Grant Erickson Signed-off-by: Lee Jones Signed-off-by: Thierry Reding

pwm: mediatek: Provide missing kerneldoc description for 'soc' arg

2020-07-30T09:27:12+00:00

Kerneldoc syntax is used, but not complete. Descriptions are required for all arguments. Fixes the following W=1 build warning: drivers/pwm/pwm-mediatek.c:57: warning: Function parameter or member 'soc' not described in 'pwm_mediatek_chip' Cc: Matthias Brugger Cc: John Crispin Cc: Zhi Mao Cc: linux-pwm@vger.kernel.org Cc: linux-mediatek@lists.infradead.org Signed-off-by: Lee Jones Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: bcm-kona: Remove impossible comparison when validating duty cycle

2020-07-30T09:27:12+00:00

'dc' here is an unsigned long, thus checking for <0 will always evaluate to false. Fixes the following W=1 warning: drivers/pwm/pwm-bcm-kona.c:141:35: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] Cc: Florian Fainelli Cc: Ray Jui Cc: Scott Branden Cc: bcm-kernel-feedback-list@broadcom.com Cc: linux-pwm@vger.kernel.org Signed-off-by: Lee Jones Signed-off-by: Thierry Reding